Glass picture-projecting device for cinematographic apparatus



y 15, 1929- w. WINZENBURG 7 L GLASS PICTURE PROJECTING DEVICE FORCINEMATOGRAPHIC APPARATUS Filed March 24, 1926 17 Mhzenhuy" PatentedJuly 16, 19 29.

UNITED STATES i 1,721,425. PATENT orrice,

WILHELM WINZENBUBG, OF KRAGENHOF, NEAR (ZASSEL, GERMANY,

GLASS PICTURE-PROJECTING DEVICE FOR CINEMATOGRAPHICAPPARATUS.

Application filed March 24, 1926, Serial No. 97,149, and in GermanyMarch 19, 1923.

' thattbc rays of light have already superposed one another completelywhen arriving at the picture window. It, however, the reflector lamp isemployed for the projection of (ha-pictures, also the shadow becomesvisible upon the dia-positive and is, consequently, reproduced on thescreen.

The object of my invention is to overcome this drawback, and indesigning the means for this purpose I have paid attention to the factthat the existing reflector lamps have proved useful for cinematographicprojection and that it is, therefore, not desirable to alter them. Now,I attain the object in view by utilizing a shadowless portion of the raypath, more especially, by directing parallel to the optical axis of thelamp the main ray of such a pencil of said shadowless, portion. Thisidea of invention can be embodied in several constructional forms, oneof which is illustrated diagrammatically and by way of example on theaccompany ing drawing. Before entering into the details thereof, Istate, that the constructional fol-n1 shown is particularly suited toproject. besides cinematographic pictures -by means of the reflectorlamp, also stationary dia-glass-pictures with the aid of a stationarylamp in such a manner that no shadow is to be seen. I

Obtaining an unobjectionable dia-projection with a search-light lamp ispossible only if a shadowless part-of the ray-path is picked out andthen this shadowless pencil paratus being now adjusted for glass pictureis used for the dia-projection. The employment of ordinary mirrors fordeflection of a pencil for the purpose of (ha-projection is known.

y The figure shows a vertical longitudinal section through a lampcasing, together with 'a side-view of the lamp 'proper and of amechanism designed for operating an additional reflector and a diaphragm(14-) according to this invention. Y On the drawing, 1 denotes the lampcas ing, and2 a horizontal adjusting rod'which is guided in a bracket 2'attached to the top of the casing. 3 denotes the additional reflectorwhich is. aflix'ed to a spindle 16 provided with an arm 17 connected bya pin 18 with two links 13 and 13', of which 13 establishes a connectionwiththe inner end of therod 2, whereas 13' establishes a connection witha bell-crank lever 19- fulcrumed at 15 to a bracket 20 and carrying acircularly curved diaphragm 14.

It is obvious that the reflector 3 and the diaphragm 14 can be movedsimultaneously by shifting of rod 2.

5 denotes the arc lamp, and 4 the reflector oi the same. When the rod 2is moved in the direction indicated by the arrow the auxiliary reflector3 will be turned out of the path of the rays coming from the mainreflector 4, and simultaneously therewith also the diaphragm 14w-ill beturned out of that path, the diaphragm being moved downwards, whereasthe auxiliary reflector is moved upwards, as will be clear without amore detailed explanation.

6 denotes a dispersing lense located above the are lamp, and 7 is athird reflector or a mirror which is adjustable and upon which isthrown, by the intermediary of the reflector 3 and the lens 6, a part ofthe 'rays coming from the reflector 4. The size and shape of the lens 6is such that the rays impinging upon the reflector 7 are deviated intothe projection axis and pass then through a collecting lens 8 to thedia-glass-picture 9. The focal distance of the lens 8 is such that therays coming from it are being collected in the (ha-objective 10. j

.11 denotes the picture window for the cinematographic projection, and12 the cinematographic objective. When the movable parts of themechanism are in the position shown in the drawing, the members 11 and12 are shut off from the rays, the approjection. I claim:

1. A glass picture projection device for cinematographic apparatus,comprising, in

shadow cast by the carbons of the said lamp, 1

a movable diaphragm located between said lamp and the picture gate inthe shadowless portion of the raypath, and means for mov ing saidauxiliary reflector and said diaphragm simultaneously, substantially asset forth. 4

2. A glass picture projection device for cinematographic apparatus,comprising, in combination, means for glass picture projection, meansfor cinematographic projection a reflector arc-lamp, a movable auxiliaryre- .flector so arranged as to be adapted to separate from the path ofthe rays emitted by said lamp a portion thatis free ofthe shadow cast.by the carbons of the said lamp, a movable diaphragm located betweensaid lamp and the picture gate in the shadowless portion of the raypathand a dispersing lens located in the lamp casing and arranged in the.path of the rays coming from the said' auxiliary reflector,substantially as set forth.

3. A glass picture projection device for cinematographic apparatus,comprising, in

. combination, means for glass picture projection, means forcinematographic projection, a reflector arc-lamp, a movable auxiliaryrefiector so arranged as to be adapted to sep= arate from the path ofthe rays emitted by said lamp a portion that is free of the shadow castby the carbons of the said lamp, a movable diaphragm located betweensaid lamp and the picture gate, means for moving said auxiliaryreflector and said diaphragm simultaneously, and a dispersing lenslocated in the lamp casing and arranged in the path of the rays comingfrom the said auxiliary reflector, substantially as set forth.

In testimony whereof I afiix my signature.

\VILHELM WINZENBURG.

